It is well known that the power supply offers multiple output voltage potential. However, since the output power of the power supply becomes higher, under the same voltage potential, the current on the power line is also proportionally increased. The current increment causes the following problems. First, the consumption of the power line caused by the current may induce waste heat and may also influence the adjustment of insulation strength, and it is also a problem that if the power line could conduct the increased current. The waste heat can be reduced by improving the conductivity of the power line (reducing impedance) or increasing the heat-dispersing area of the power line. As to the insulation strength of the power line, it should be matched to the prescribed safety standard, and further, the current rating is also decided by the material or structure of the power line. Therefore, in the past, as designing the power supply with different output voltage standards, it always has to select a suitable power line conforming to the standards, especially when customizing the product where the output standard and corresponding product standard should meet the customer's requirement. However, in practice, it actually is very uneconomic to develop different product standards for every customer, and as mounting (or welding) the components on the PCB of the power supply, every time the output standard changes, the PCB layout also must be varied (because practically it is impossible to desolder the welded components and the new layout must be mounted on the new PCB). Therefore, time, labor and cost all are wasted.
Some disclosures had solved the above described problems, such as, R.O.C. patent No. M308435, entitled “An improvement of output structure for power supply”. In this patent, an extended output structure of power supply is provided for extending out multiple power lines to conform to multiple peripherals connected to the power supply. Herein, the power lines in the power circuit (20) of the power supply are divided into motherboard power lines (31) and peripheral power lines (32), wherein the peripheral power lines (32) are connected to an I/O terminal of a circuit board (322). The I/O terminal of the circuit board (322) has 4 to 8 sockets for connecting wires, so that through the sockets on the circuit board, the peripheral power lines can be connected to each peripheral outside the case. However, the additional circuit board outside the power supply has fixed position and assembling fashion which actually might cause inconvenience, and for some customized power supplies, it also might be insufficient in space for further disposing the circuit board. Besides, because the motherboard power lines (31) and the peripheral power lines (32) are configured to “connect to the power circuit (20)”, when the power circuit and the peripheral power lines do not conform to customer's requirement or the requirement changes, the structure can not be varied easily, so that the materials and the manpower are still wasted. Consequently, although this prior art improves the connection convenience between the power supplies and the peripherals, the variation in output standard and the convenience for replacing power lines are still unconsidered.